There are just over 400 species of cockroach in Australia of the approximately 4000 that exist worldwide. Of these 400, in Queensland the native species are of little concern to householders. However, three introduced species, the American cockroach, the German cockroach and the Australian cockroach are pests in the household and known carriers of disease. Despite its name, the Australian Cockroach is introduced, possibly from Asia.

A dead cockroach up-close

Identifying Characteristics

All cockroaches have an oval and flattened body, and a thorax covered by a large plate which extends partly over the head. Both the American and the Australian cockroach are large, approx 40mm in length and reddish brown in colour. The American cockroach has indistinct brown markings on the thorax and no yellow edges on the fore wings while the Australian cockroach has a yellowish thorax with dark edges and yellowish edges at the base of the forewings. In contrast the German cockroach is much smaller at about 10mm in length, a pale colour with two dark bars running lengthways down the thorax.

Life Stages

Most cockroaches, including these three species, lay seed like brown eggs in capsules which they hide in crevices and the folds of fabric. The young develop gradually, resembling the adults but of course, much smaller in size. They are active from hatching but lack wings which they develop as they grow.


All three species are found in houses and buildings, although the American cockroach will inhabit compost heaps, industrial areas and sewers. They favour warm and humid environments, and look for dark cracks and crevices in which to hide during the day. They stay close to food and water sources such as kitchens, lunch rooms, and other food handling areas. When found outside of these areas, it indicates a heavy infestation. They are spread in packaging and cartons being moved from one location to another.


Cockroaches are active at night, feeding on food scraps, fermented food, decaying matter, glues in items like book bindings or even soiled clothing.

Detrimental Effects to Humans and Property

Cockroaches contaminate their environment with droppings, empty egg cases, vomit and other secretions. Infestations cause anxiety and revulsion to humans, can worsen symptoms in asthmatics, and damage property in extreme cases. Through their contact with human food and food preparation utensils, they can indirectly spread diseases.

Eradication/Control Mechanisms

Treating dark areas, crevices etc. with chemicals is very effective as cockroaches only leave these areas to forage. There are also likely to be multiple occupants of these areas, increasing the effectiveness of the treatment. This must be supplemented with proper human hygiene. Cleanliness makes cockroaches vulnerable to eradication as they are forced to forage further for food and water, increasing their exposure to treated surfaces.

The team at Bob Gunn Termite Solutions are trained, experienced and licenced to advise on cockroach pest control and guarantee the effectiveness of their treatments.

To book your next cockroach treatment, call us today on 07 3286 9877.